The Study On Functional Traits Of Dominant Shrubs In Qin-Ba Mountains And Loess Plateau

Study for response strategies of plants to environmental changes has become a cutting-edge research of ecology. Response mechanism between plant functional traits and environment vary from different research regions and scales. We measured leaf stable carbon isotope composition ((?)13C), leaf nitrogen concentrations(LNC), leaf carton concentrations(LCC),specific leaf area(SLA), leaf dry matter content,(LDMC), Stem density(SD), Root density (RD),Stem Ash(S Ash) and Root Ash (R Ash) of35species at13sites in Qin-Ba Mountains (QBMs) and Loess Plateau (LP) where their environmental factors are quite different such as temperature, moisture and so on. We analyzed the correlation among functional traits and the regularity between traits and environmental factors. The main results are as follows:(1) As latitude increased and average annual temperature reduced, LNC increased in Qin-Ba Mountains,but LNC distributed as a inverted bell-shaped along average annual precipitation in QBMs. Meanwhile, LNC and SD were higher and SLA was lower at more rainfall regions and low latitudes in Loess Plateau. And LCC, SLA increased with average annual temperature increased in LP.(2) Shrub species in QBMs had complicated interrelations:LDMC negatively related to813C、LNC、SD or S Ash, but positively related to RD; RD positively related to LCC and SD; LCC positively related to LNC; R Ash negatively related to RD and positively related to S Ash. In Loess Plateau, interrelations of SD-813C and SLA-LCC were negative; RD was higher at a given SD. It demonstrated that functional traits of plants in different regions coordinated variation and had split response strategies.(3) There were no significant differences of functional traits between different functional types of shrub in QBMs. At the same time, the common species in QBMs and LP performance discrepant response to different environment. In addition, results of variance analysis to traits of plants in QBMs and LP showed (?)13C,SD and RD of9selected traits had large variations between two regions. Those three traits were good indicators for plants zonal distribution.In summary, the traits in leaf, stem and root of plant in QBMs and LP showed diverse trends under the influence of environmental factors and also the interrelationship between the traits. And those plants behaved different adaptive strategies to environment.Meanwhile,(?)13C,SD and RD had a good indication for plants zonal distribution in QBMs and LP.